1. Field of the Invention
The present invention relates to network access servers (NAS) used in enabling access to various network services, and more specifically to a method and apparatus for replenishing a user account with more access resources needed for accessing such services.
2. Related Art
Access providers (e.g., an internet service provider (ISP)) may control the extent to which users can access various services (e.g., movies, songs, on-line games, etc., hereafter “network services”) provided from various networks. Such control may be used, for example, to bill (force payment) users for the network services accessed.
In a typical scenario, an access provider uses a network access server (NAS) which forwards or blocks packets related to a user (or a group of users) based on various access resources a user is entitled to use. For example, an access resource may specify that the user is permitted to access a specific movie for 2 hours only. Accordingly, the NAS may forward the related packets only for 2 hours.
At least to control access to network services, an access provider may maintain a user account associated with a single or a group of users. The user account may be used to specify the access resources (time permitted to access a service or network, number of total bytes permitted to transfer, etc.) a user is permitted to use while accessing various network services. Systems such as billing servers, which enable a user to pre-purchase (or specify other payment options) desired access resources, may be used to specify the access resources users are permitted to use.
A user account may need to be replenished with more access resources when a user is accessing network services. For example, a user account may specify that the user is permitted to access a movie for only 2 hours and the user may be on verge of exceeding such permitted time (while continuing to watch the movie). It may be desirable to enable the user to continue to access the network service, possibly by enabling the user to replenish the user account by purchasing more access resources.
In a prior approach, when such replenishment is required for a user, a NAS may intercept a HTTP request (for a web page from the same client system from which a network service is being accessed) and redirect the user to a web page which indicates the access resources which require replenishment for continuation of access to the network service. One problem with such an approach is that a HTTP request may not be timely received from a client system, or even worse the user may not be using a corresponding software (typically web browser). Accordingly, such a solution may not be suitable in several environments.